What you want to do with system is run a comand called glomosim, and pass an input file. So the first part in the example I gave you was to a program called glomosim.exe, if this isn't an executable you need to substite the command with whatever you want to run, not cmd.exe, so the general form of what you want to run is:

So you need to substite the path to the golomsim program and the path to the input file in the above example. In Re^2: system sub routine with windows7 I give some code to use to produce any errors. I have no idea what glomosim is, how it's executed, but if you substitute these values for the correct paths to the executable and input file we can provide further help if required.

I have misunderstanding :( !.
maybe I can't make my question be clear to you.
the glomosim is a network simualtor , whatever , when I want to execute the file (data.in). I go to cmd.exe and write the command (glomosim data.in) and press enter.
So glomosim here is a command , as you have said, I want to pass this command (glomosim data.in) and run it on cmd.exe from perl.
when I write :

I got the error :
can't spawn "cmd.exe" : No such file or directory at run_FtpGen.pl line 71
system glomosim c:\glomosim\bin\data.in failed ...
I am beginner with perl and using windows7, so sorry for my many questions. :)
Thank you

Went to join the gridlock to see it
Held an eclipse party
Watched a live feed
I cn"t see tge kwubosd to amswr thus
I tried to see it, but 8000 miles of rock got in the way
What eclipse?
Wanted to see it, but they wouldn't reschedule it
Read the book instead